Our understanding of human visual cognition is based almost exclusively on studies of image-based stimuli. The human visual system has evolved to perceive and interact with real objects, yet almost nothing is known about behavioral and brain-based responses to real-world complex objects, or how these differ from comparatively impoverished image displays. The long-term goal of this research is to elucidate the full set of underlying mechanisms that are engaged in real object perception. The research will provide unprecedented insight into, and comprehensive scientific understanding of, psychological and neural systems implicated in this domain. The objective of this application is to understand how and why real-world stimuli, compared with images, influence cognition, behavior, and neural responses. The central hypothesis is that real objects are processed and represented differently to images because they are relevant for genuine goal-directed action, and neural systems that are engaged in action are also recruited in the service of perception and cognition. The central hypothesis is formulated on the basis of preliminary behavioral, neuropsychological, and fMRI data produced by the applicants. The rationale for the research is that studying richer stimuli that match the characteristics of objects that are encountered in everyday life will fundamentally improve our understanding of cognition, and, thereby, expand the generalizability and translational value of scientific knowledge to real-world environments and settings. The central hypothesis will be tested by pursuing three specific aims: (1) Determine how perception and recognition processes differ for real objects vs. images; (2) Determine how memory processes differ for real objects vs. images; and (3) Determine how visual exploration and attention differ for real objects vs. images. These fundamental processes will be examined using behavioral and/or fMRI studies in healthy observers and neuropsychological patients with perceptual deficits. The studies involve real life-sized objects with natural surface texture, compliance, and weight. The objects have a definite size, distance, and location from the observer, and most importantly, they afford genuine actions such as grasping and manipulation. The studies employ novel and innovative experimental devices, procedures, and paradigms, designed for presenting large numbers of real objects in rapid succession in the laboratory and the fMRI scanner, under controlled viewing conditions. Together, these stimuli and techniques will serve as benchmarks for researchers and clinicians exploring real-object effects on behavior and neural coding. The contribution of the proposed research is that it will elucidate fully the underlying processes and mechanisms that are engaged in real-world cognition, and will shift current research paradigms that focus on images to more ecologically valid stimuli. This contribution is significant because it will reveal, for th first time, how the integrated workings of the perceptuo-motor system fundamentally shape visual cognition, why these systems should be studied with real graspable stimuli, and how their joint activity influences and improves performance.